The Prime Minister's former strategy guru has claimed the EU is a "secretive" and "impenetrable" organisation that does not work to Britain's advantage.

Today he told the Times: "If he were a member of the public or a backbench MP, or a junior minister or even a cabinet minister, I’m certain he would be for leave.

“That’s who he is. As prime minister he sees it from a different perspective, and that’s perfectly reasonable . . . but I think that if he didn’t have that perspective he would be for Leave.”

Mr Hilton also suggested that plans for a referendum had been on the agenda since the Conservatives were last in opposition.

Steve Hilton claims that David Cameron would back Brexit if he was not the Prime Minister

“There was a strong constituency in the senior leadership and policymaking team for leaving the EU," he said.

"I recall a meeting where we sat down and I remember saying, ‘Right, if our assumption is that we think it’s in Britain’s interest to leave the EU — and I think we’re all agreed about that option around this table — then we need to have a plan for how we make that a realistic part of our policy platform.’

"The intellectual basis for leaving the EU is there in all the arguments that we were making.”

In an interview with The Telegraph Mr Hilton said the Prime Minister and Chancellor were “clearly happy among the elites of Europe” and are “part of the technocratic elite" rather than challenging it.

Asked if Cameron and Osborne felt “happy among the elites of Europe,” he said: “Yes – they are clearly amongst the big elites of Europe and to me those big elites are the enemy of the kind of country I want to see.

"That is why we find ourselves on very different sides of the argument.”

He said that Mr Cameron – who came to power in 2010 saying he wanted to give power away – and Mr Osborne are now “part of the technocratic elite”.